<template>
    <div>
<p>count值: {{ count }}</p>
<button @click="add">加</button>
</div>
<template>

    <script setup>
        import {ref} from 'vue';
        const emit = defineEmits(['updateCount']);
        const count = ref(1);
        const add = () => {
            count.value++;
            emit("updateCount", 2);
        };
    </script>